Lifting jack



March 11, 1924. 1,486,179

T. J. BIRD LIFTING JACK File May 15 1922 Patented ill, 1224..

warren stares THDEEAS JAIEES BIRD, 0F SEATTLE, WASHINGTON.

MFTING AGE.

Application filed M94715,

To all whom it may concern:

Be it known that THOMAS J. Brno, citizen of Canada, residing at Seattle,in the county of King and State of Washington, has invented certain newand useful Improvements in Lifting Jacks, of which the following is aspecification.

lhis invention relates to lifting jacks, and has for its object theprovision of a screw-jack of the floor-type of novel form andconstruction which will be operative to perform the functions of a jackfor automobile, house moving, railway track-work, and for other uses, ina particularly direct, expeditious and eliective manner.

A further object of the invention is to provide actuating mechanism ofsimple and advantageous arrangement and design whereby the actuatingforce applied to the appa' ratus is utilized in increased power withoutunduly decreasing the speedy performance of its work.

A still further object of the invention is the provision of novel.supporting devices in which the objects to be lifted are engaged wherebythe ack can be readily and quickly fitted in operative position with aminimum of labor and time expended.

It is within the province of the disclosure to improve generally and toenhance the utility of devices of that type to which the presentinvention appertains.

With the above and other objects in view which will appear as thedescription proceeds, the invention resides in the combination andarrangement of parts, and in the details of construction hereinafterdescribed and claimed, it being understood that, within the scope ofwhat is claimed, changes in the precise embodiment of the inventionshown can be made without departing from the spirit of the invention.

In the accompanying drawings Fig. 1 is a view in side elevation of ajack embodying my invention. 1

Fig. 2 is a plan view of the same partly broken away to disclose theinterior mechanism thereof.

Fig. 3 is a view principally in vertical section of the same.

Referring to said views, the reference numeral 5 indicates a cast-metalbase of substantial construction of generally cylindrical configurationand formed with an extended annular ledge 6 about its lower perimeterwhich may be extended upon one side in a 1922. den-tail H0. 581,65d.

lip as at 7. A cylindrical casing 8 integral I with said base isarranged concentrically thereon and formed with an interior chamber 10leaving a circular opening 11 in its bottom in the vertical axis of thechamber and said base extending through to a recess 12 on the undersideof the base.

The bottom surface 13 of said chamber is suitably formed to provide abearing for a circular roller-bearing composed of a plurality of taperedrollers 15 each having rounded ends 16. 17 indicates a gear-Wheel formedwith gear-teeth 18 on its peripheral edge and having upper and lowersurfaces 20 and 21, respectively, of suitable configuration to conformto rollers, such as. 15. A vertically arranged cylindrical post 22extends in a reduced shank 23 through a central aperture in saidgear-wheel 17 wherein a key 25 connects them to rotate in unison. Saidpost is provided with a shoulder 26 supported on the upper side of thewheel 17 and extends thereabove and above the casing where it is formedwith screw-threads, as indicated at 27. Rollers 28 are superposed uponthe gear-wheel 17 in substantially the same manner as indicated withreference to 'the rollers 15 and a cover-plate 30 is proand 36 arerespectively disposed which sup port a crown gear-wheel 37 on a bearing:pin 38. Said gear-wheel 37 has gear-teeth 40 on its peripheral edgewhich are in mesh with the teeth 18 of gear-wheel 17 and inclined teeth41 on its crowned edge in mesh with a driving bevel-pinion 42 mountedupon mandrel &3 supported in a yoke 4A secured to said brackets 35 and36. An operating shaft 45 is connected to said mandrel by a universaljoint 4:6 and may be manually actuated by a crank-handle 47 while theoperator may support said shaft by a loosely mounted spool 48 that maybe grasped by one hand.

A lifter-member cooperating with the above described devices is composedof a substantially cylindrical body 50 having an axially arrangedscrew-threaded bore 51 adaptable to receive the screw 27. A saddie 52 atthe to of the litter is arranged to receive an ax e or any object thatis to he lifted, Adjacent the bottom of the body said lifter is formedwith an arm 53 extending atsubstantially right angles thereto swingable,dependent leg 57 formed with a terminal hook 58 in which an object to belifted which is at a level too low to be reached by either of the othersimilar devices 52 or 55 maybe received. Also said leg may be swungoutwardly to get under an object that otherwise would be difiicult toreach with a jack.

The operation of my improved jack will hereadily understood from theforegoing description taken in connection with the accompanyingdrawings. With the lifter in its lower-most position, as indicated inFig. 1, the jack is placed. under the object to be lifted or slidablymoved thereunder through pushing the jack by means of the shaft 45. Theack is placed thereunder in such position that either of the supportingelements 52, 55 or 58 will receive the said object. The shaft is thenactuated causing the bevel-pinion 42 to actuate the gearwheel 17 throughintermediate gear 37 and thereby rotate the post 22 which throiwhreaction ofits screw-threads 27 with tie opposing screw-bore 51 of thelifter-body transferre through the post 22 to the gear-- 1 earts wheelthrough said circular shoulder 26 and is thence borne upon 'therollers15 there below which take up said-load evenly and distribute the samethroughout the base. In the event that a load is to be borne upon theoil-center portion of the jack, such as the depression or hook 58, anytensional tendency will be transmitted throughout the anti-frictionalelements 15 below and 28 above the gear-wheel 17 in such manner to moreequally distribute the strain and to insure the continuance of asmooth-running transmission of the power and an efficient reduction offriction.

While I have shown my invention through choice as being actuated bygears I do not wish to be confined to such construction as the1nvent1on= may undergo certain changes and modifications to suitparticular purposes such as the substitution of a rack and to saidshaft. within the chamber and having inclined upper and lower surfaces,and roller bearings arranged between the upper and lower surfaces of thegear and the top and bottom of the chamber respectively, said rollerbearings occupying the full space within the chamber in both directionsbeyond the gear, and means carried by the jack and arranged beyond thechamber for driving cooperation with said gear.

In testimony whereof I aflix my signature.

THOMAS JAWS BIRD.

